Anderson, Leroy. The Typewriter. Composition completed 9 October 1950, first performed 8 September 1953. New York: Boston Pops, Decca Records. "Anderson composed the melody for symphony and pops orchestras; William Zinn and Floyd Werle arranged it for string orchestras and wind bands respectively." Available on YouTube, e.g. here.
From Wikipedia entry: "The typewriter is considered a percussion instrument, and the typewriter part is usually performed by a percussionist or drummer [...]." The portable mechanical typewriter is also iconic and epitomizing for The Mechanical Age. If one can track the movement of the Modern into the postmodern in pinball machines ceding player time to video games and their descendants, even so we can track it in the world of office work and home communications from mechanical typewriters to electric typewriters to electronic typewriters, to personal computers.
The sound of a typewriter fitting into orchestral music — and in performance the image of typist and typewriter amidst the orchestra — is both amusing and a kind of highly positive symbol — "epitome"? — of the machine fitting into the human world, and a representative part of the arts of the human world making space for it and inviting its voice into a simultaneously literal and symbolic symphony.
See Henri Bergson on "Laughter" and note academic lore on a comedy and laughter figuratively rooted in in incongruities and paradoxes: here the apparent incongruity and comic paradox of a typist and typewriter among the musicians and their instruments.
RDE, ChadD, 27Aug20